WE’VE all heard of the “glass ceiling”: the invisible barriers to advancement that face women and people from ethnic minorities. But what has been given a lot less attention in the past couple of decades is the enduring “class ceiling” – the barriers preventing working-class people from rising up the career ladder.

It’s been convenient for the privileged classes to ignore social inequality and instead co-opt able members of minority groups into their elite circles. For too long policy-makers have been seduced by the myth that Britain is, essentially, a classless meritocracy. That, to quote Tony Blair in 1999, “the class war is over”. It isn’t.

This is about more than just the attainment gap in education, which is where the problem first presents itself – most obviously in the failure of white working-class boys (girls and children from ethnic minorities generally perform much better in our schools). According to a book out this week from economists Sam Friedman and Daniel Laurison, even when people from working-class backgrounds perform well ,and make it into prestigious jobs, they earn on average 16 per cent less than colleagues from more privileged backgrounds. It’s the class pay gap.

The Class Ceiling – Why It Pays To Be Privileged involved hundreds of interviews with people in elite occupations and, surprise surprise, the top performers tend to come from privileged backgrounds. Only around 10 per cent of people from working-class backgrounds (three per cent of the population) make it to the top 20 per cent of occupations, and they earn a lot less when they get there, even if they have better qualifications. Moreover, they often have to change their accents, cultural identity and even their beliefs.

The stuffy, old boys network may largely be a thing of the past, but social networks and attitudes remain hugely important in recruitment to elite occupations. In many areas, like the media and academia, a kind of studied informality, and even a liberal outlook, are the calling cards of the new privilege.

Thus articulate, middle-class Allegra, with her veganism and smart casual clothes, is more likely to get ahead on Channel 4 (reputedly the poshest workplace in Britain) than awkward Edward, with his ill-fitting suit and liability to talk of “coloured people” instead of “people of colour”. These linguistic niceties are professional death.

A confident manner, polished appearance and a discreet sense of entitlement constitute a “cultural display”. It marks you out as suitably qualified to enter the elite – someone who will just “fit in”. This display is often mistaken for merit and intelligence. Anyone who has taught in universities will know how misleading these appearances can be. Scottish students are often dismissed as dour and uncommunicative when they’re really just being economical with the bull****. Perhaps there’s a Jock ceiling somewhere.

Living in London is certainly a huge advantage, given that most elite jobs are located there and housing is prohibitively expensive for outsiders. The bank of mum and dad allows privileged young people to work in low-paid, or unpaid, internships. Then there’s generational carry over, the “following wind”. The children of doctors and lawyers are up to 24 times more likely to get into these same jobs, a figure the authors describe as “staggering”.

This is partly a question of culture – parental expectation combined with insider knowledge. You just absorb a lot about medicine in a doctor’s family. We can’t stop the children of lawyers studying law – that would be absurd. Nor can we prevent artists, writers or musicians from following in the family footsteps. Or Hilary Benn becoming an MP like his father, Tony. But in a sense these cultural factors, while important, are a diversion from the central issue: which is the persistence of inter-generational economic inequality.

This is the social elephant in the mobility room – and it isn’t new. Alan Milburn and the board of the Social Mobility Commission resigned in disgust two years ago over social inequality and the state’s inability to recognise it. It is not just about culture and manners – about social barriers, and about “talking proper”. The reality is that since the 1980s Britain has become deeply socially divided through relentless and accelerating inequalities of wealth and power.

Working-class women and people from ethnic minorities are doubly handicapped, since they often have racial or gender prejudice to cope with in addition to social inferiority. But it is class that unites the less privileged. What is implicit in the Class Ceiling is that the focus of recent years on gender and race has rather obscured true big picture of social inequality.

This is reflected in law. The Equalities Act of 2010 “protected” sexual and racial groups against discrimination and unfairness, but not social class. This now looks like a serious failure. There was an unwritten assumption in the equalities legislation that social mobility exists, but is being denied only to people from certain ethnic and gender minorities. The law thus inadvertently privileged certain cohorts against the biggest disadvantaged group of all.

For far too long, public policy has been based on a casual assumption that economic inequality is not a problem so long as there is equality of opportunity. That’s it’s just about hard work, or intelligence. But it isn’t, and it never has been.

Brexit is not about social class as such. But we can’t ignore the aggressive politics of the “left behinds” in provincial England. They feel that the metropolitan elite has no interest in their welfare unless they become like them. Social mobility is a joke. We have seen in America how working-class outsiders – the deplorables and and white nationalists – can react in dysfunctional ways to their marginalisation. These divisions are toxic.

The Class Ceiling is one of the most insightful works on the dynamics of inequality since Pickett and Wilkinson’s The Spirit Level a decade ago. It makes uncomfortable reading for middle-class liberals. However, the metaphor is wrong, implying that if we removed the invisible barriers all would be well. We really need to be looking, not at the glass, but at the ceiling itself.

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